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Bisl 15. technology

1.
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6.
M
any animal species use tools, and some,
such as crows and apes, can even create
them. But only our species has taken this
ability to such an extreme that it can be said that
we maintain an evolutionary symbiosis with these
tools. In other words, our ability to develop
complex tools increased our intelligence, allowing
us to manufacture even more complex tools. This,
in turn, launched a new phase in this cycle, and
after several million years it finally led to the
modern human, who continues to develop tools
that will likely continue to transform the species.
Of course, this history has not always followed a
linear path. In the 9,000 years since humans
discovered agriculture and cattle farming, many
inventions were discovered many times and
forgotten nearly as many times. Today we are
surprised to learn that the Romans knew about
concrete and that they had taxis and hamburger
stands or that the Greeks developed the basic
principles of the locomotive and the steam engine
(although, oddly enough, they never combined the
two to invent the railroad). We have developed
the most absurd theories to explain the
construction of the pyramids in Egypt or the moai
of Easter Island. This winding history, with steps
forward and steps backward, can be explained
thus: technical inventions are a specific response
to the specific needs of a given human group, and
when these needs or the people who needed to
meet those needs disappear or change, the
inventions associated with them also disappear or
change.
A
few centuries ago, the creative ability of
human beings took a major leap forward
when tools associated with craft and
empirical techniques began to complement
science, thus systematizing the methods of
production. This is how modern technology
emerged, allowing improved preservation not just
of know-how but also of the economic, social, and
cultural aspects involving this know-how. Once
tool making ceased to be something that was
passed on from master craftsman to apprentice
and became an organized set of procedures and
knowledge accessible to a specialized community,
the human ability to invent new tools underwent
an explosion similar to the one it experienced
9,000 years earlier. Virtually overnight thousands
of objects appeared (and would continue to
appear) that changed our way of seeing and
understanding the world—the clock, which
allowed us to divide time and set a new pace for
our lives; the printing press, which allowed
knowledge to be spread beyond a privileged few;
the refrigerator, which enriched and diversified
our nutrition practices; the cinema, which opened
up the possibility of dreaming while awake; the
Internet, which erased borders and distances; and
robotics and artificial intelligence, which led us to
question our definition of being human. With the
emergence of technology, you could say that our
lives are surrounded by marvelous objects.
T
his book takes us on a journey through
some of the inventions that have changed
our everyday habits and our understanding
of the world that surrounds us. It is not meant to
provide a thorough or definitive view. The creative
abilities of human beings will always make such a
task incomplete. Here we look at the
revolutionary technologies that mark milestones
in the development of technology. We also
examine inventions that have become so essential
in our daily lives that it is difficult to imagine the
way the world was prior to their existence. We
look at technologies that have lengthened our life
expectancy and improved our health. We also
explore inventions that are just now beginning to
show their potential and are opening up worlds
that not even the most imaginative science-fiction
authors could have foreseen. It is surprising to see
the degree to which many of these technologies
are related, like a rich tapestry of invention and
creativity that make us grow as a species, expand
our culture, satisfy our needs, and shape us as a
society.
An Endless
Inventiveness
NANOROBOT
Microscopic device that is formed
by arms scarcely 10 nanometers in
length. In the photograph, it is
shown transporting a drug through
the interior of an infected cell.

7.
Daily-Life Applications
T
echnology has been an
integral part of our daily lives
for several decades now,
drastically affecting us in
many positive ways. Liquid
crystal displays (LCD) form a part of a
plethora of industrial and consumer
appliances, such as automated teller
machines, home appliances, television
equipment, and computers. The
scanner, calculator, and fax
revolutionized the worlds of work and
study, and photography, the DVD, and
the camcorder allowed us to stop time
and save unique moments forever. Our
THE iPOD 8-9
LCDs 10-11
3-D MOVIES 12-13
THE DVD 14-15
NINTENDO WII 16-17
THE DIGITAL CAMERA 18-19
VIDEO 20-21
MICROWAVES 22-23
SCANNERS 24-25
ATHLETIC SHOES 26-27
LIVE TV
Thanks to television we can
watch events as they happen,
like this girl who is watching
the liftoff of Soyuz 9 in 1975.
daily lives are altered by technology. We
see it wherever we look; it offers us the
things we have always sought: comfort,
entertainment, and the tools to make our
daily tasks easier.

8.
The iPod
TECHNOLOGY 98 DAILY-LIFE APPLICATIONS
One of the most notable features of
the attractively designed iPod is its
ability to store high-fidelity recordings. In
a size slightly larger than the palm of a
person's hand, users can store up to 80
GB of data.
Since its launch in 2001, the iPod has become smaller, lighter, and more efficient. It
now has a color screen, and its maximum storage capacity is 16 times greater than the
first model. The iPod spawned a flourishing business in accessories, and it has become a
symbol of an entire generation. Today it is the most popular portable multimedia player.
Endless Entertainment
Evolution
Music
The iPod can store more
than 20,000 songs in its
80 GB version (and up
to 7,000 songs in its 30
GB version).
5 GB
iPod
2.4 inches (6.1 cm)
Original iPod
The first version of the
iPod held 5 GB of
information.
2001
Mini iPod
Up to 6 GB
capacity.
Discontinued.
2004
U2 iPod
This model was launched in
partnership with the band
U2 and Universal Music Group.
2004
iPod Nano
The successor of the iPod mini.
Smaller and lighter, with a
color screen. Holds up to 8 GB.
2005
iPod Shuffle
The smallest model, it
weighs only 0.5 ounce (15
g) and has no screen.
2005
5G iPod
Holds up to 80 GB;
2.5-inch (6.3-cm)
color screen.
2005
iPod Touch
A touch screen in full
color with access to
YouTube
2007
4inches(10.4cm)
Video
The 80 GB version can
store and play more
than 100 hours of video
in various file formats.
Images
Stores more than 25,000
images. Plugged into a
home theater system, it can
display the images with
musical accompaniment on
a large screen.
Back
cover
Speaker
The partnership between Apple and Nike resulted in an iPod that
provides the athlete with preprogrammed music to accompany
an exercise regimen, even as it monitors performance variables,
such as pace, speed, distance covered, and calories burned.
FOR SPORTS ENTHUSIASTS
A sensor is placed
on the left shoe to
collect data during
the physical
activity.
The iPod Nano is
connected to a
wireless receiver. The
iPod receives the
data gathered and
sent by the sensor.
While enjoying music
chosen for its beat,
the user receives a
performance report,
which is stored in the
iPod for reference.
Receiver
Sensor
Control panel, called
a Click Wheel
Controller (a
copyright of Apple)
Each time the iPod connects with a computer, it uses its address book
and its calendar, one of its most useful applications.Contacts
Main plate LCD-TFT screen (in this 1.5 inch [3.8 cm] model)
0.2
(0.6)
3.5(8.89)
Dimensions in inches (cm)
Games
The iPod comes with
four games, but it is
possible to download a
large number of games
from iTunes.
The interior of a 2 GB iPod Nano illustrates the
complexity of this multimedia player. Chips,
circuits, plates, ports, and even a thin liquid crystal
display fit into a space only 3.5 x 1.5 inches (9 x 4 cm).
Complexity in a Small Container
321
Data-
entry port
Earphone
jack
Cover
Flash
memory
Battery
T
his fifth-generation, sophisticated multimedia
player, introduced by Apple in 2001, currently lets
users store and play up to 80 GB of music, video, and
images, encoded in many formats; it also allows them to
transfer information from both Mac and PC computers.
The iPod can download new files from iTunes, an
exchange software developed by Apple. This software
serves as a complex data manager, allowing customers
to purchase files from a library of more than 3 million
songs and 3,000 videos.
1.5
(4.06)

11.
14 DAILY-LIFE APPLICATIONS
The DVD
TECHNOLOGY 15
Optical discs (CDs and DVDs) are read by a
laser beam to obtain information. This
information is transformed into a binary electric
signal that is later interpreted and converted into
sounds, images, and data.
Reading with Light
This comparison traces the evolution of the compact disc—especially its storage capacity.
From the CD to Blu-ray
From the CD to Blu-ray, information storage has become
denser, and the wavelength of the reading beams has
become shorter.
1 millimeter = 1,000 micrometers ( m)
1 micrometer = 1,000 nanometers (nm)
* Inverted view
* Inverted view
* Inverted view
* Inverted view
CD
Length of
the shortest
pit: 0.9 m
DVD
Length of the
shortest pit:
0.4 m
Plastic
polycarbonate
Aluminum
reflecting
layer
Plastic
polycarbonate
A binary pattern,
composed of ones and
zeros, is formed by the
transitions between pits
and flat areas. A large pit
represents a certain
number of consecutive
zeros. A change in height
represents a one.
HD DVD
Length of the shortest
pit: 0.204 m
BLU-RAY DVD
Length of the shortest
pit: 0.15 m
Profiles*
Laser emitter
generates a laser beam of
a specific wavelength.
Mirrors
guide the ray by working in
coordination.
1
2
Direction
In order to read the disc,
the laser beam must strike
the surface of the disc
perpendicularly.
3
Lens
focuses the laser beam
before it reaches the surface
of the disc.
4
Reading
The laser beam strikes the
disc's reflective surface. The
reflection varies according
to the pattern of pits on the
disc's surface.
5
7
1
6
2
3
4
5
Prism
changes the direction of the
laser beam that reflects from
the disc and contains the
data read from the disc.
6
Photodiodes
translate the variations in the
returning laser beam and
convert them into a digital
signal.
7
Because blue light has a shorter wavelength than
red light (which is used in CDs and DVDs), a blue
laser makes it possible to read smaller pits, which
accounts for Blu-ray's greater storage capacity.
Resistance to scratches and dirt
Maximum video resolution
Supported formats
Transfer rate in megabits per
second (Mbps)
Maximum capacity (single layer)
Maximum capacity (double layer)
Laser wavelength
No
--
No
576 pixels
No
1,080 pixels
Yes
1,080 pixels
875 MB
--
789 nm
6
4.7 GB
8.5 GB
650 nm
11.1/10.1
15 GB
30 GB
405 nm
36.55
27 GB
54 GB
405 nm
36/54
CD DVD HD DVD BR-DVD
VCD and
SVCD
DVD, VCD,
SVCD,
MPEG-2
MPEG-2, VC-1
(based on WMV),
H.264/MPEG-4 AVC
MPEG-2, VC-1,
MPEG-4 AVC
Blue laser
T
he storage capacity of a DVD, six times that of a traditional CD, has revolutionized the way digital
data is organized and stored in the decade since its appearance in 1997. The DVD explosion
resounded in the world of home movies thanks to its capability of storing entire feature films,
bonus material, and subtitles (in various languages) on only one disc. The evolution of technology,
however, has not stopped with DVDs. Recent years have seen the introduction of discs able to hold 12
times the data of the DVD.

12.
32 feet (10 m)
Nintendo Wii
TECHNOLOGY 1716 DAILY-LIFE APPLICATIONS
is the brain of Wii. Its slim
design (a mere 1.7 inches [4.4
cm] wide) plays the games that are
loaded on standard 4.7-inch (12-cm)
discs, accepting both single- and
double-layered discs.
System
has an IBM PowerPC processor,
ports for four controllers, two USB
ports, slots for memory expansion,
stereo sound, and support for playing
videos on panoramic 16:9 screens.
Connectivity
The console connects with the
Internet (it includes Wi-Fi wireless
connection), from which it can
receive updates 24 hours a day to
add or upgrade features.
The Movement Sensor
A player's movements are
detected by means of a flexible
silicon bar inside the Wiimote.
This bar moves within an electric
field generated by capacitors.
The player's movements cause
the bar to change the electric
field. The change is detected and
transmitted to the infrared
sensor, which translates it into
the movements of the virtual
character.
The Console
The Wiimote, the Wii's remote, differs from traditional game
consoles by looking more like a remote control than a videogame
controller. It was developed to be useable with just one hand.
Magnetic field Magnetic field
Capacitor
Silicon
piece
Fixed
base
Fixed
base
Silicon
piece
Capacitor
Movement
The Wiimote
Wii consoles are
manufactured daily by
Nintendo. In preparation for
the Wii's launch in Japan,
400,000 units were
manufactured (an
unprecedented quantity for a
new console), all of which
were sold within a few hours.
Controllers for
every occasion
Nunchuck
It is connected to
the Wiimote and
introduces
additional options
for specific games,
such as two-
handed boxing or
changing
viewpoints in
target shooting.
Security strap
allows for the safe use
of the controller with
one hand, keeping the
Wiimote from falling
or slipping.
Players
Up to four players
can participate
simultaneously in
the same game.
All of the sensors
use Bluetooth
wireless
technology.
Traditional
controller
This controller is still
necessary for playing
with games from earlier
Nintendo consoles.
Vibrator
generates vibrations appropriate
for the situation, such as when
shooting a gun or hitting a ball.
Infrared
emitter
Port is used to add peripherals, such as the
Nunchuck, which not only enhances its
functions but also its traditional controller.
1.2 inches
(3.08 cm)
1.4 inches
(3.62 cm)
5.8inches(14.8cm)
Button
Dimensions
Infrared sensor
detects the player's
position from up to a
distance of 32 feet
(10 m) or 16 feet (5
m) during use of the
pointer function
(used to indicate
points on the screen).
Console
Internal speaker
reproduces sounds, such as
gunshots or the clash of swords.
LED light
indicates which player is active
in multiplayer games.
Console buttons (holding down
both buttons activates Wiimote's
discovery mode, which can be
used to set it up to work with a
Bluetooth-enabled PC)
250,000
The “excessive enthusiasm” of some
early players caused worries about the
weakness of Wiimote straps, so
Nintendo decided to replace them with
safer ones and modified 3,200,000 units.
Enthusiasm
W
ith the launch of Wii, Nintendo tried to cause a revolution in
the world of video-game consoles. Wii, the fifth generation of
Nintendo's video-game consoles and part of the seventh
generation of video gaming, is the successor to Nintendo's GameCube.
Wii has several features intended to help a wider audience play video
games and get closer to the world of virtual reality. Among them are
sophisticated wireless commands that transfer tactile effects, such as
blows and vibrations; infrared sensors that detect the position of the
player in a room and convey the information to the console; and
separate controls for each hand. Wii was a commercial success from
the moment of its launch in December 2006.

14.
Video
Magnetic layer
STRUCTURE OF THE TAPE
The tape is wound
on a guiding roller.
HI8 DIGITAL 8 MINI DVDVD
Different systems and media are used
for different applications, depending
on the final quality desired.
FOR PROFESSIONAL USE
DV cam
Digital betacam
REPRODUCTION AND EDITING
What is recorded can be viewed by
connecting the camera to a TV, a video
recorder, or a printer to print photographs.
Black cover
Film base
STORAGE
Data is stored as bytes. The image can be reproduced
without losing image or audio quality. The level of
detail is greater in digital than in analog.
DIGITAL TAPE
is small, which
makes it ideal for
portable cameras.
Digital tape
combines magnetic
tape with the data
compression made
possible by digital
technology.
Diamond-like
carbon layer
Lubricating layer
The head records and
plays back by means of an
electromagnet.
Carries the electric signals
that represent image and
sound
RECHARGEABLE
BATTERY
Up to six hours
A built-in
microphone allows
for the inclusion of
high-quality audio.
1965 1976 1979
From Analog
to Digital
Technology
199519801975 2000
Several formats
2.598
inches
(66 mm)
1.889
inches
(48mm)
The particles of the
magnetic tape form
varying patterns.
C
reated at the end of the 1950s, video
was originally a technology linked to
television. Before its invention,
programs had to be broadcast live,
with all of the inconveniences
associated with such a live
event. Very soon, new
possibilities were found for
video, and in 1965, the Korean
artist Nam June Paik made
the first art video. In 1968,
Sony developed the first
portable video camera. On the
other hand, the launch of the
VCR system by Philips in 1970
made viewing movies at home a
part of everyday life.
IMAGE RECORDER
Digital cameras allow for capturing
video as well as for taking pictures,
using the same technology.
CCD chip
The image is formed on this
sensor by the light that
passes through the lens, and
the image is transformed by
the sensor into electric
signals.
Lens
Light source
An internal program translates the light
data (analog information) into the binary
system (digital information).
The image will be
comprised of cells
called pixels.
It can be used directly
in a computer.
1.
2.
3.
VIDEO 2000
This system of magnetic-tape cassettes
used both sides of the tape, similar to
audiotape. It was distributed by Philips
until 1988.
Duration 8 hours
VHS SYSTEM
The VHS system became a standard
for recording and viewing
videocassettes. Home viewers and
video clubs became popular.
DVD
Philips and Sony introduced this digital
disc. It can store every type of digital file,
including high-definition video. A laser is
used to view it.
Duration of up to 240 minutes
SUPER 8
Eastman Kodak developed an 8 mm-wide
film inside a plastic cartridge. The film was
used with a portable camera and a
projector, and the format was very
popular for home movies.
Duration 3 minutes
WEBCAMS
These small digital cameras connected to a
computer can take photographs and record
short videos. Connected to the Internet, they
can be used in real time.
BETAMAX
Sony developed magnetic tapes that were
of high quality but had little recording
time. It continued to be manufactured for
high-quality recordings until 2002.
Duration 60 minutes
VHS
The Video Home System was developed
by JVC. Its advantages included re-
recording most movies on a single tape,
though some image quality was lost.
Duration 60 to 90 minutes
25%
more quality than the
analog formats
Lens
Manual
focus ring
LCD ROTATING
SCREEN
is used as a monitor
or viewfinder. It can
be rotated to
different angles.
TECHNOLOGY 2120 DAILY-LIFE APPLICATIONS

15.
How a Microwave
Oven Works
What it does is heat food by using
high-frequency electromagnetic waves.
The Electromagnetic
Spectrum
Electromagnetic energy has waves
that have specific length and
frequency within a continuous range known
as the electromagnetic spectrum.
In Communications
According to the frequency and length of
the wave used, the microwaves are also
used in radio, TV, and cellular telephones.
Radio control
controls and assigns the
functions related to radio
waves. The geographic area in
which the service is rendered
is called the coverage area.
Base station
The station contains
radio equipment that
issues electromagnetic
waves from
communication antennas.
Cells and telephones
Each cell has a
transmitting base station,
which has multiple
channels for the
simultaneous use of
dozens of phones. When a
user passes from one cell
to another, the phone
leaves the frequency it
was using and takes an
available frequency in the
new cell.
Electric plug
Transmits low-
frequency electric
current
Magnetron
The magnetron transforms electric
energy into electromagnetic waves
(high-frequency microwaves).
Microwave oven
The waves are distributed uniformly within
the cavity, generating heat by the friction of
the molecules present in food and liquids.
MICROWAVES INFRARED
RADIATION
VISIBLE
LIGHT
ULTRAVIOLET
RADIATION
X-RAYS GAMMA RAYS
The greater the
wavelength, the
less the energy.
The frequency is a measure
of the number of times that
the electromagnetic field
oscillates in one second.
RADIO WAVES
UNITS OF MEASUREMENT
Length of the wave Meters
Frequency Hertz
TV WAVES
1 2
3
1 2 3
THE ERS-1 SATELLITE
ORBITING EARTH
It was launched from the Guyana
Space Center in July 1991, and its
mission was to map the
atmosphere and surface of the
Earth by using microwaves.
In the winter, we usually rub
our hands together to generate
heat; this principle is used in
microwave ovens.
T
his is the name given to electromagnetic waves found between radio
waves and the infrared spectrum. They have many applications,
the best known being the microwave oven, developed in 1946
from research conducted by Percy Spencer. Cellular-phone
technology, cable TV and Internet, radars, and wireless protocols
such as Bluetooth also use microwaves to transfer and receive
information.
Microwaves
22 DAILY-LIFE APPLICATIONS TECHNOLOGY 23
CELLULAR TECHNOLOGY
allows communication between users whose
locations are unknown or who are mobile. To this
end, an infrastructure with base station antennas
as its sole visible element must be set up.
ELECTRIC CURRENT
The smaller
the length of
the wave, the
greater the
energy.
METERS 105
104
103
102
101
100
10-1
10-2
10-3
10-5
10-6
10-7
10-8
10-9
10-10
10-11
10-12
10-13
10-14
10-15
10-16
Oscillation

16.
Scanners
The scanner that
is used daily is
the bar-code
reader.
The scanner comes from the phrase “to scan.” An image
is scanned by a head that transforms it into digital data.
How an Image Is Digitized
THE ORIGINAL
can be any document with a
flat surface, such as a
photograph, a paper document,
or a page in a book.
SCANNER HEAD
analyzes a photograph and
converts it into digital
information.
A system of
mirrors and lenses
concentrates this
light in the optic
sensor.
It is placed
facedown on the
transparent screen.
LINE BY LINE
The scanner head reads one
small horizontal strip at a time.
Once a strip is
finished, the head
moves and reads
the following one.
Each strip can be less than
0.00039 inch (0.01 mm) thick.
DIGITAL ARRAY
The data from the sensor are placed in an array
that is used in reconstructing the image.
IN THE COMPUTER
The image, converted into numerical
data, is displayed on the computer. The
image can be retouched and enhanced
through specialized computer programs.
OPTIC
SENSOR
DATA
CABLE
MIRRORS
LUZ
Other Types of Scanners
COMPUTERIZED
TOMOGRAPHY
takes a series of X-
rays of the body from
different angles.
BAR CODES
A small scanner with a laser reads
each bar and assigns a number
according to its thickness, thus
reproducing a numerical code.
Original
Light
source
Lens
Mirrors
The cover can be
removed to scan
originals that are
very thick.
2
HOW IT WORKS
The optic sensor
transforms the received
light into electric
impulses. These are then
digitized (transformed
into data).
3
The image is made
up of a very fine grid
formed by elements
called pixels.
Each pixel is assigned a
number that represents its
color and brightness.
HEAD GUIDE
The scanner head
moves along the
length of this guide.
PRECISION MOTOR
must be able to advance
and stop the head every
hundredth of a millimeter.
1.
2.
3.
4.
Sensors
Skin
The computer
reconstructs
the image.
DIGITAL FINGERPRINTS
are made by tiny electric
sensors that react in contact
with skin.
The complete set of
sensors reproduces the
fingerprint.
Light bounces against
the original and takes
on its colors.
1
24 DAILY-LIFE APPLICATIONS TECHNOLOGY 25
S
everal technologies that digitize, read, detect, and trace images, objects, or signals can be
grouped under this term. The better known are computer scanners and bar-code scanners,
but scanners are also used in medicine, biometric identification, security systems, and
detection of radio frequencies. Some computer scanners incorporate text-recognition software,
which can digitize printed, typed, or even handwritten text. This capability has been very useful in
digitizing a great amount of material at universities and libraries; however, it has also encouraged
pirating in publishing.

17.
Interior
Many different materials
are used. Models for
running must satisfy
requirements for cushioning,
stability, and ventilation.
TOE CAP
provides a good fit
and molds to the
foot. Depending on
the sport, it offers
protection or low
weight and
breathability.
HIGHLY
ENGINEERED MESH
allows air but not dirt
to pass through.
SIDE PANELS
For ventilation
METALLIC MESH
Ultrathin to ward
off dust
13ounces
(390 g)
IS THE WEIGHT OF THIS
ATHLETIC SHOE.
3
TECHNOLOGY 27
T
hese shoes were already used in ancient
times in Mesopotamia and Egypt, but they
became widely used in the last decades of the
20th century. The first athletic shoes appeared in
1893. They were made of canvas and were used
so that sailors did not need to walk with shoes
along the docks. Today athletic shoes
incorporate true technological advances
designed to meet the needs of each sport. For
instance, athletic shoes have begun to
incorporate air chambers, located between the
insole and the external covering of the sole that
act as cushions to protect the foot.
Athletic Shoes
INSOLE
reduces excess heat and friction.
Made of foam rubber or EVA to
provide extra cushioning.
COUNTER
Made of a semirigid material,
the reinforcement covers the
heel internally and can prevent
instability.
FASTENING SYSTEM
Shoelaces, zippers, or
Velcro. They must fasten the
shoe in such a way that the
foot can flex in movement.
IMPACT
When running, the
movement of the foot
is cyclic. It requires the
cushioning of the heel,
the part of the foot
that undergoes
repeated impact.
LANDING
With support, the foot
naturally rotates inward
(pronation). The stabilizing
elements prevent excessive
pronation.
IMPULSE
The pressure shifts
from the heel to the
front of the foot,
which is compressed
as it pushes off the
ground.
The heel hits
the ground
with a force
three to four
times the
weight of the
body.
Biomechanics of Racing
RUNNING
SOCCER
BASKETBALL
TENNIS
HIKING
CROSS
TRAINING
RUGBY
HANDBALL
MIDSOLE
joins the front toe cap
(to which it is sewn)
with the insole (to
which it is glued).
CHASSIS
Used for reinforcement
The openings provide
airflow.
CUSHIONING
SYSTEM
Viscous cushioning
material, placed in
the area of impact
for running
LATERAL MOVEMENT
is one of the most dangerous movements for sports
people. A good shoe controls the natural movement of the
foot. There are three types of footstep.
SUPINATION
needs flexible
shoes and
cushioning.
2 percent of
the population
NEUTRAL
Correct and
without any
disorders
24 percent of
the population
PRONATION
leans toward the inside
because of a person being
flat-footed or overweight.
74 percent of the
population
Track shoes include
nails, and soccer shoes
include cleats that can
sink into the soil for a
better grip.
SOLE
can be made of solid or natural rubber.
Some include air bubbles that compress
when impacted. Each sport requires a
different design whose main function is to
provide a good grip on the surface.
Flexibility
Grip
26 DAILY-LIFE APPLICATIONS
INNER SOLE
Their function is to provide
comfort and stability and to
support the foot. They must
be light and flexible.
TOE GUARD
Protection from rubbing
against the toe cap
1 2

18.
Breakthrough Inventions
I
n the history of technology, there
are milestone inventions that
radically changed the world and the
way we perceive it. Many of these
inventions, such as cinematography
or the radio, are the realization of the
longtime hopes and dreams of humankind.
Others, such as the Internet, the cellular
telephone, or GPS, have transformed the
way we communicate and have
dramatically shortened distances between
people. Inventions such as the printing
press and the computer chip led to the
dramatic development of the arts and
sciences, enabling in turn the appearance
of more new technologies. Others, such as
computers, have not only become
indispensable tools, but they have also led
us to question the nature of intelligence.
SKYSCRAPERS 30-31
THE CELLULAR TELEPHONE 32-33
GPS 34-35
THE COMPUTER CHIP 36-37
THE COMPUTER 38-39
THE INTERNET 40-41
CINEMATOGRAPHY 42-43
TELEVISION 44-45
THE PRINTING PRESS 46-47
THE LASER 48-49
HOLOGRAPHY 50-51
THE FIRST COMPUTER
The Electronic Numerical Integrator and
Computer (ENIAC) was invented in the
1940s and weighed 30 tons, occupied 1,800
square feet (170 sq m), and required a total
of 17,468 electronic valves for its operation.

20.
32 BREAKTHROUGH INVENTIONS
The Cellular Telephone
F
ew inventions have had as widespread an impact as the cellular phone. In just two-and-a-half
decades, the cellular phone has become extremely popular around the world and almost
indispensable for populations in the developed world, to the point that sales already surpass one
billion units a year. The latest cell phones, in addition to being small, portable, and light, are true
workstations that far exceed their original function of keeping the user connected at any time and place.
TECHNOLOGY 33
1
2
28 ounces
(780 g)
Providers divide an area into a
system of cell sites. Each site
has an antenna that detects the
presence of a particular cell phone in
its area and identifies it through the
phone's unique code.
Communication
In addition to being a telephone and having such traditional features as a calendar,
calculator, and camera, a smartphone incorporates advanced computing capabilities
for connecting to the Internet through Wi-Fi and to other devices through Bluetooth.
Smartphones
Cell sites detect the movement of a cell phone; as the signal weakens at one site,
it becomes stronger at another. This movement allows seamless communication,
even during high-speed movement from one cell site to another.
In Motion
Since the first cell phone appeared on the market in 1983,
mobile telephones have become smaller and, at the same time,
they have incorporated dozens of new features, such as Internet
connectivity, picture taking, and videoconferencing; the mobile
telephones also play music.
The Evolution of the Cell Phone
is the weight of the Motorola
DynaTAC 8000X, which was the
first commercially available cellular
phone. More recent models weigh
less than 2 ounces (50 g).
3 billion
is the approximate number of
cell phone subscribers in the
world, according to the latest
data. This number is equal to
almost half of the world
population.
Calling
When a number is dialed, the antenna
at the local cell site identifies the
caller and the called party. It then
transmits this information
to the switch.
The switch
The switch maintains a database of all the cell
phones that are turned on and their cell-site
locations. It then locates the position of the
called party and sends the information
to the appropriate cell site.
3 Connecting
The local cell-site
antenna establishes
communication with the
requested cell phone.
INTERNATIONAL
CALLS
As is the case with landline
phones, international
communications are facilitated
with the assistance of satellites.
When a cell phone user
moves away from the
service provider's
network, the service can
be provided by another
carrier. The phone is
then in roaming mode.
1983
Motorola
DynaTAC 8000X
Simon Personal
Communicator
Motorola
StarTAC
Nokia
7110
Sharp
J-SH04
Samsung
SCH-M105
Kyocera
QCP6035
Panasonic
P2101V
Motorola
ROKR
1993 1996 1999 1999 2000 2001 2001 2005
First cellular
phone
First PDA/cell phone
Added applications such as a
calculator, calendar, address book, etc.
First clamshell cell phone
Design reaches the cell
phone
One of the first to use
Wireless Application
Protocol (WAP)
First cell-phone
camera (released
only in Japan)
First MP3 cell
phone
First Palm-
powered cell
phone
Among the first third-
generation cell phones (with
videoconferencing)
First cell phone
with iTunes
iPhone
2007
has a 3.5-inch
(8.9-cm) touch
screen and Wi-Fi
Web access.

22.
1
2 4
653
What It Is
It is a thin silicon wafer that
measures less than half an inch
(1.3 cm) across and can contain several
million electronic components.
THE INVENTOR
Jack Kilby developed the
first integrated circuit in
1959. His invention had a
huge impact on the
development of the
electronics industry.
Jack Kilby
Electrical engineer from
the United States. He was
awarded the Nobel Prize
for Physics in 2000.
TECHNOLOGY 37
W
ithout this small electronic device, the majority of new technologies from the past
few years would not exist. The computer chip is present in myriad objects used every
day. Despite its limited dimensions, each chip contains thousands or millions of
interconnected electronic devices (mainly diodes and transistors) and also passive components
(such as resistors and capacitors). Its invention was made possible with the discovery that
semiconductor elements could accomplish the same functions as vacuum tubes but with a
much superior performance and at considerably lower cost.
The Computer Chip
36 BREAKTHROUGH INVENTIONS
0.02 inch
(0.6 mm)
is the size of the smallest
computer chip in the
world. It is used to detect
counterfeit bills.
INTEGRATED CIRCUITS
are mounted on printed
circuit boards and are
connected via copper
pathways.
TRANSISTOR
Etched in the silicon, the
transistor is a very
effective semiconductor
device and amplifier, but
microscopic in size. The
smallest ones measure
50 nanometers.
TRADITIONAL
TRANSISTOR
Simple capsule
SIZE REDUCTION
Continuing improvements in the techniques of
computer-chip fabrication have allowed the
development of ever-tinier electronic components.
0.2 inch
(5 mm)
0.3 inch
(7 mm)
ACTUAL
SIZE
0.5 inch
(1.3 cm)
0.5 inch
(1.3 cm)
CHIP
can contain
millions of
transistors.
contain the
computer chip
GOLD WIRES
are soldered to chip
terminals and connect
them to the pins.
HOW TRANSISTORS WORK
Transistors act like electronic switches that are activated
and deactivated by means of an electrical signal.
An electrical signal
is applied.
The negatively charged
(doped) silicon has atoms
with free electrons.
The positively charged
(doped) silicon has atoms
lacking free electrons.
The positively charged silicon receives free
electrons from the electrical signal, establishing
a current flow between areas of negative silicon
and thereby activating the circuit.
Negative silicon
The electrical signal
is interrupted.
The current
does not flow,
and the circuit
is deactivated.
PINS
are small metallic legs
that connect the
integrated circuit to
the printed circuit.
YEAR
1971
1978
1985
1989
1993
2000
MODEL
4004
8086
386
486
PENTIUM
PENTIUM 4
TRANSISTORS
2,250
29,000
275,000
1,180,000
3,100,000
42,000,000
ACTIVE CIRCUIT INACTIVE CIRCUIT
First Integrated CircuitEvolution of the
Computer Chip
0.6 inch (1.5 cm)
GERMANIUM WAFERS
contained a single transistor
and other circuit components
of an audio oscillator.
GLASS SUBSTRATE
This is where the
components are placed.
WIRE
CONNECTORS
0.4 inch
(1.2 cm)
PACKAGE
Plastic or
ceramic casing
Where They Are Found
PRINTED CIRCUIT BOARDS
are used inside electronic
devices. They are tiny and
placed on top of a copper
sheet that is laminated
onto a plastic board.
COPPER
PATHWAYS
SOME APPLICATIONS
HOME Microwave ovens, digital clocks
OFFICE Computers, calculators
COMMUNICATIONS Telephones, TV, radio
TRANSPORTATION Air and land traffic control
MEDICINE Diagnostic equipment
ENTERTAINMENT Audio, video games
MILITARY Weapons
CHIP
A layered silicon
wafer that contains
electronic
components

23.
The Personal Computer
is made up of various interconnected devices (the
hardware) and programs (the software). The core is a
very powerful microprocessor that contains all the devices
and is installed on the motherboard.
1
2
3
4
5
6
TECHNOLOGY 3938 BREAKTHROUGH INVENTIONS
2
3
4
5
6
1
F
rom the huge calculating machines that occupied entire rooms
to today's home and laptop models, computers have
revolutionized how we see the world and relate to it. Today our
everyday lives are characterized by information technology, whether
for recreation, work, study, or communication. Already under
development are quantum computers and so-called molecular
computers, which are biocomputers that use DNA as the basis of
their circuits and that have the ability to replicate themselves.
The Computer
PROGRAM
is the component most closely related to
the user. It is also known as application
software. It allows the user to accomplish
tasks, such as processing text and images,
performing calculations, managing
databases, and using the Internet.
OPERATING SYSTEM
Windows is the one
most commonly used. It
presents the system in a
user-friendly way, using
icons, folders, and
windows.
ACCESS DEVICES
KEYBOARD
It is used to enter data
(numbers, letters, and
symbols) by sending coded
signals to the microprocessor.
When a key is pressed, a
contact is closed.
OPTICAL MOUSE
controls the placement of the
cursor in the computer's
graphic interface. It registers
any movement of the mouse
and calculates the coordinates
of the movement.
UNDERSIDE
A video camera
registers
movement.
A light-emitting
diode (LED)
illuminates the
surface beneath it.
COMPUTER TOWER
is the case that holds the main
components.
STORAGE DEVICES
are used to save information or
transport information to
another computer.
MOTHERBOARD
The main printed circuit board to which all
other hardware components are connected
ROM MEMORY
(Read Only Memory)
Used to store the basic startup instructions
for the computer
EXPANSION SLOTS
allow for the insertion of circuit boards to
incorporate more devices.
CD/DVD READER/RECORDER
reads and also records CDs
and DVDs.
HARD DISK
saves programs and folders
as permanent, magnetically
recorded data.
FLOPPY DRIVE
reads and records information on
flexible floppy disks (diskettes).
MONITOR
The images are formed by tiny cells
called pixels, which use the additive
primary colors red, green, and blue.
High-resolution monitors can have an
array of up to 1,920 x 1,200 pixels.
INPUT
Data enters the computer through a keyboard, mouse,
or modem and is interpreted by the appropriate circuit.
MICROPROCESSOR
controls all computer functions. It processes the
entered data and carries out the necessary arithmetic
and logic calculations.
RAM MEMORY
temporarily stores all the information and
programs used by the microprocessor.
PROCESSING
Data can travel back and forth from the CPU to the
RAM several times until processing is complete.
STORAGE
Data is sent to a storage device (for
example, the hard disk).
OUTPUT
The information on the monitor is updated
through the video card.
CONNECTORS
are used to connect
peripheral devices,
such as a modem,
scanner, or printer.
PARALLEL
PORT
Essential Components
USB PORT
Key
Conducting
surface
Printed
circuit
How a
Computer Works
Example of the routing of information
during a basic process
LAPTOP MODELS
have a rechargeable battery
and smaller dimensions. They
basically have the same
features as a PC.

24.
The Internet
I
s a worldwide network where interconnected computers of every type can exchange
information. The social impact of the Internet is comparable to the invention of the printing
press, enabling the free flow of information and access to it from anywhere in the world. With
the appearance of blogs, the world of editing and journalism has become democratic, since virtually
anyone can publish their own texts, images, and opinions.
TECHNOLOGY 4140 BREAKTHROUGH INVENTIONS
HOW IT IS SET UP
The Internet is a worldwide network in which one
participates through a service provider, which
receives, saves, and distributes information using
its computer “server.” The user's computer
connects to the Internet using a variety of
methods, programs, and devices.
TRANSMITTING COMPUTER
The message is sent from here to its
destination through the modem.
MODEM
Its name comes from
Modulator-Demodulator.
The outgoing information
is modulated and sent via
a conventional telephone
line or through a
broadband connection.
ROUTER
This device sends out information packets to their
destination, always choosing the shortest route (the one
with the least traffic) by using the TCP/IP protocol.
TCP/IP PROTOCOL
TCP separates the information into individual packets
and assigns each one an identifier and an IP address.
The latter determines the route each packet will follow.
THE BROWSER
is a program that allows the user to see documents on the World
Wide Web and to go from one document to another using the
hypertext transfer protocol (HTTP). The most common browsers
are Internet Explorer, Netscape, and Firefox.
A WEB SITE OR WEB PAGE
contains a series of documents
written in hypertext markup
language (HTML) combined with
other, more sophisticated
languages, such as Java and Flash
animation.
ELECTRONIC MAIL
travels from one computer to
another through e-mail servers. It
can carry attachments, such as
photos or text documents.
SEARCH ENGINES
are tools used to find information
available on the World Wide Web.
They function like a database that is
constantly being updated by robots
that prowl the Web and collect
information. The most commonly
used search engines are Google and
Yahoo; they also offer other services
to their users, such as e-mail and
news updates.
CHAT
This service allows a group of
users to communicate with each
other in real time. It started out
only in written form, but it is now
possible to transmit audio and
video images via webcams.
VOICE OVER IP
is a system that allows a computer to
communicate with a regular telephone
anywhere in the world, bypassing normal
telephone charges. It requires an Internet
connection and a program that enables this
type of communication.
INTERNET ACCESS
The user contacts an Internet service provider (ISP)
using a modem, which may connect through phone lines
or cable; it may also connect wirelessly.
Intermediate
routers
THE WEB
is made up of all
the connected
systems.
Information
packets
Transmitting Information
These interconnected systems share information internally
and with external users, forming networks. Information
travels from one computer to another through such a network.
RECEIVING COMPUTER
converts the information it receives.
Communication
s satellite
Satellite antenna
Local telephone
switchboard
Internet
server
Internet
serverPC user
Modems
PC user
Modem
PC user
Local
telephone
switchboard
International
telephone
switchboard
International
telephone
switchboard
Satellite
antenna
1 2
3
TYPES OF CONNECTIONS
Fiber-optic cable
Transmits light signals.
It is faster and has higher
bandwidth (capacity).
Wireless
Satellite and radio-wave
transmission through
microwaves or cell phones
DSL
uses telephone lines to
provide high-speed
connections.
Coaxial cable
Used for cable TV and
Internet
4
5

25.
TECHNOLOGY 4342 BREAKTHROUGH INVENTIONS
Cinematography
S
ince the middle of the 19th century, the desire to produce moving images has resulted in the
development of a large variety of mechanical devices, such as the praxinoscope and the zoetrope.
The appearance of celluloid film allowed real images to be captured to show movement.
The introduction of sound was a revolutionary innovation, even more so than the introduction
of color. The idea of three-dimensional images has also been pursued, with mixed results.
Today IMAX technology allows viewers to become immersed in the film they are watching.
FRAMES
are 10 times larger than a
traditional motion-picture frame,
providing better image definition.
MOVIE SET
French director,
screenwriter, and actress
Nicole Garcia on the set
of her movie Every Other
Weekend (Un Week-end
sur deux).
Traditional
35-mm
frame
IMAX
frame
The First Projection
Systems
Roger Bacon invents the magic lantern, the
first step toward the modern projector.
The Lumière brothers invent the first
projector, inspired by a sewing machine,
and hold a screening in Paris.
Color movies appear. The Technicolor camera
superimposes three films—red, blue, and
green—to produce a color image.
1400
1895
1932
The light source
was an oil lamp
Objective lens
Light beam
Projected
image
Image support
Crank for
advancing the
film strip through
the projector
Movie reels
Lens
Wheels supported
the film strip and
helped advance it
Object lens:
expanded the film
frame up to 35 x 24
inches (90 x 60 cm).
IMAX Technology
is the most advanced motion-picture projection system. Invented in
Canada, it is used in more than 228 movie theaters across North
America and Europe. As of today, only four theaters have all three
projection systems: IMAX, Omnimax, and IMAX 3-D.
SOUND
27,000 watts of power
Sound passes through small
holes in the screen and travels
throughout the whole theater.
SEATS
The seats recline and the viewer
cannot see the edge of the
screen, creating the feeling of
being immersed in the movie.
THE PROJECTOR
The system provides greater
image stability.
THE SCREEN
is metallic, hemispherical, and
white. It wraps over the
seats like a dome. It takes
four minutes just to open it.
Omnimax
180º
projection
Projector
Diameter: 100
feet (30 m)
FLAT IMAX
uses a silver-colored flat screen, which
reflects projected light more strongly
than a white screen.
IMAX 3-D
Viewers must wear glasses that allow
them to see in three dimensions.
70 feet
(21 m)
95 feet (29 m)
Equivalent to
a seven-story
building
Projector
Screen
Size of screen in
theaters today
Varieties

26.
Each line is made up of points of
different brightness. By convention,
they are split into the three primary
colors: red, green, and blue.
VIDEO
The image is divided into a
series of horizontal lines.
SOUND
is codified and broadcast using
the same method as the one
employed in FM radio.
1.
2.
3.
VIA AIRWAVES
Employs a system
similar to AM and
FM radio
VIA SATELLITE
Uses high-frequency
radio waves. The signal
can cover an entire
country.
VIA CABLE
A coaxial or fiber-optic
cable permits the
reception of a large
number of channels.
BA
TECHNOLOGY 45
T
he origins of television date back to 1884, when Paul Nipkow invented a rotating scanning
disk camera for capturing moving images, but it was only in 1936 when the first modern TV
broadcast was made in England. The invention of radar during World War II reduced the
costs of this technology, making it accessible to the general public. In spite of its slow beginning,
television became an important medium for communication, greatly influencing the opinions,
behaviors, and imagination of several generations. Today analog technology is being replaced by
digital technology, and three-dimensional television is at the experimental stage.
Television
TAPING
The camera captures images
through its lens and sound
through a microphone.
TRANSMISSION
Images and sound are transmitted together through radio,
coaxial cable, or fiber-optic cable.
Each frequency is split between the image (AM) and the
sound (FM).
RECONSTRUCTING THE IMAGE
Each image is like a
still photograph of a
single moment.
American television
broadcasts 30 frames
per second at 60 hertz
(60 times per second),
while European
television broadcasts
25 frames per second
at 50 hertz.
Each image
correlates to an
instant in time.
The images are
integrated in the
brain, resulting in the
illusion of continuous
movement.
Each image is shown
twice. The 30 (25)
frames per second are
seen as 60 (50) fields
per second.
In interlaced-format
broadcasts, only half
of the display lines of
the image are swept
with each field. One
field delivers the odd-
numbered lines, and
the next delivers the
even-numbered lines,
and so on until the
entire picture is
drawn by interlaced
scan.
RECEPTION
RECONSTRUCTING MOVEMENT
44 BREAKTHROUGH INVENTIONS

27.
Different Systems
These processes all require a
printing plate or other printing
surface but differ in the way they
separate the printed area from the
nonprinted area.
Digital Printing
Systems
eliminate the need for film (used in
traditional printing processes).
These machines can accomplish all the
steps of production up to delivery of the
finished product. The development of the
digital printing systems began in the 1990s.
593 Around 1450 1796 1886 1904 1990
SERIGRAPHY
The printing
surface is a
mesh screen.
LETTERPRESS
The printing
surface may be
rigid or flexible.
FLEXOGRAPHY
The printing
surface is
flexible.
ROTOGRAVURE
The printing
surface is a copper-
coated cylinder
with tiny pits, or
cells, for the ink.
OFFSET
uses an aluminum
printing plate covered
with photosensitive
material.
1.
2.
5.4.3.
TECHNOLOGY 4746 BREAKTHROUGH INVENTIONS
T
he social and cultural impact of the invention of the printing press is comparable to the
development of language and the invention of the alphabet. It made possible the
establishment of a scientific community, in which knowledge can be communicated with
ease. In addition, it made the notion of authorship of a text more meaningful, the book
became a popular object, and the dominance of Latin ended, definitively displaced by local
tongues. According to some theorists, such as Marshall McLuhan, the press fostered the
preeminence of words over the image, changing the way we understand the world today.
The Printing Press
Nondigital systems require
a separate printing plate
for each color, and each
color is printed separately.
INKING SYSTEM
The printers use four basic ink colors
to obtain the majority of colors.
Special color inks (metallic,
fluorescent, Pantone) can also be used.
CYAN
MAGENTA
YELLOW
BLACK
PRINTING
Ink is transferred to the
paper. The machine is
equipped with a rod
that flips the paper over
for two-sided printing
(front and back).
PAPER
ENTRANCE
INKS INTERNAL
DENSITOMETER
regulates how
much ink is
transferred.
In China, multiple
copies of an image
or text were made
by carving wood.
Technological Advances
PRINT DRUMTURNING
A FOLD
CUTTING AND
FOLDING
The printed spool of
paper is cut, and the
sheets are arranged so
that the pages line up
in proper order,
including the cover.
PAPER
ROLL
Metal
molds
OFFSET
is a printing technique
based on lithography
that uses plates for
the page surface.
Currently offset is the
most frequently used
printing technique.
DIGITAL
Computers
eliminate the use
of printing plates.
Digital printing
integrates all
production steps in
one single machine.
LINOTYPE
is similar to a
typewriter.
It allowed mechanized
typesetting and
composition, which
until then had been a
manual task.
LITHOGRAPHY
Invented by Alois
Senefelder in 1796,
lithography is a
printing method
based on the property
of immiscibility of ink
and water.
MOVABLE TYPE
Johannes Gutenberg
invented a printing system
that used metal movable
type. Words were
assembled letter by letter
and could be used to
compose different pages.
BINDING AND
FINISHING
The pages are stapled or
glued together, and knife
blades trim off the excess
border to the
publication's final size.
INFORMATION
INPUT
The information is
sent from here. The
original document is
a digital file whose
data is sent directly
to the printer.
HEWLETT
PACKARD
INDIGO PRESS

28.
The Laser
B
ased on quantum mechanics, the laser is an optical device that emits a
well-defined photon beam. The result is monochromatic light that can
have various properties depending on the purpose for which it is
designed. The name is an acronym for Light Amplification by Stimulated
Emission of Radiation. When lasers were invented in 1960, they were
called a “solution in search of a problem.” They have since resolved
myriad “problems” in the sciences, the arts, medicine, industry, and
everyday life, becoming an essential tool in modern society.
TECHNOLOGY 4948 BREAKTHROUGH INVENTIONS
THE INVENTOR
Total-reflection
mirror
Atoms in the
ruby rod
Quartz
flash tube
Partially
reflecting mirror
The light from the lamp
stimulates the atoms.
Ordinary red light
is emitted by the
atoms.
Photons that are
reflected in the
interior stimulate
other photons.
This process
results in a cascade
of photons.
The laser beam
(photons) exits the rod
with a uniform
wavelength, which can be
adjusted to produce
beams of different colors.
Theodore Maiman
Year
Type
It was the first working laser,
and it was built using a ruby
rod measuring just a few
centimeters across.
This generates different types
of energy. External stimulation
with heat, electricity, or light
can result in the conversion of
static energy to kinetic energy.
Inner orbit
Low energy level
Outer orbit
Energy levels depend on the
proximity of the orbits to
the nucleus. The greater the
distance, the higher the
energy level.
ORBITS AND THEIR ENERGY LEVELS
ELECTRIC LIGHT
The amount of light emitted by a
small lamp is greater than the amount
of light emitted by a laser, but the
light does not have a specific
wavelength and direction.
THE LASER IN ASTRONOMY
The Starfire Observatory in New Mexico uses an
advanced laser system to stabilize star images,
eliminating the twinkling effect.
Lasers are also used in astronomy to make
measurements. In this way the distance from the Earth
to the Moon was measured with great accuracy.
THE LASER LIGHT
is directed and has a
predetermined wavelength.
Its power resides in the
concentration of photons
within a narrow beam.
Laser light exists in nature. It is
produced by the light of some stars
that act on surrounding gases.
AN ELECTRON'S LEAP
LIGHT GENERATION
When an electron is
struck with a burst
of energy, it can
momentarily jump to
a higher-energy
(outer) orbit.
Electron
High level
When the electron
returns to its
original orbit, it
releases energy in
the form of a
photon.
Energy
Low level
ATOM
Electron
Orbit
Nucleus
The ruby rod is shown
with its atoms at rest.
1960
Ruby laser
Atom
Nucleus
Light
energy
How a Beam Is Formed
Light is amplified by stimulated emission
of radiation.
THEORETICAL PRINCIPLES
A laser is based on the
behavior of atoms, which are
in constant motion and can
achieve different states of
excitation.
1 2 3 4 5 6
The inner surface of the
cylinder is polished to
reflect the dispersed light.
A few photons
escape.
Most photons are
reflected again.
Some photons
are lost.
The light is composed of
particles (photons) with a specific
level of energy. The process by which
photons propagate outward to form the
laser beam is called radiation.